Precision grinding wheel dressing device for pantograph machines



Oct. 30, 19451 1 NAcHEMov 2,388,216

PRECISION GRINDING WHEEL DRESSING DEVICE FOR PANTOGRAPH MACHINES Filed Dec. 7, 1944 INVENTOR,

Patented Oct. 3 0, 1945 Y PRECISION GRINDING WHEEL DRESSIN DEVICE FOR PANTOGRAPH MACHINES Leonard Nachemov, New York, N. Y., assigner to Abraham J. Sossner, Theodore T. Sossner, and Nettie Sossner, a copartnership doing business as Sossner Steel Stamps, New York, N. Y.

Application December '7, 1944, Serial No. 566,991

7 clanes.k `(o1. 12s-i1) The present invention'relates to grinding wheel dressing devices and more particularly for use in the dressing of grinding wheels for precision grinding profiling machines of the pantograph type, which employ a follower co-operating with a pattern and a grinding wheelperforming on the work; the contour of the pattern profile being similar to the contour of the profile tobe performed on the work.

, In this type of machine, the diameter of the4V pattern follower must bear a denite relationship to the diameter of the grinding wheel. As the grinding wheel wears, they diameter of the follower to be used need be smaller, and is therefore changed from time to time, and being definite at any time, requires that the diameter of the grinding wheel used be, or be made to such dimension whereby the mandatory relationship of the respective diameters of the follower in use an the grinding `wheel be maintained.

The principal object of this invention is to provide a novel and improved device for dressing the grinding Wheel to the prescribed size it must have with respect to the follower used at any time.

Another object is to provide a novel and improved device of the character set forth, which when once set to Vdress the grinding wheel in proper relation to a follower of particular size, needs no further adjustment to accomplish proper dressing of the grinding wheel with respect to any smaller follower chosen for operation.

l A further object of this invention is lto provide a novel and improved device of the type mentioned, which is simple in construction, easy to use, cheap to manufacture, and ecient in carrying out the purposes for which it is designed.

Other objects and advantages will become manifest asV this disclosure proceeds.

In the accompanying drawing, forming part of I this application, similar characters of reference indicate corresponding parts in all the views.

Fig. 1 is a plan view of a device embodying the teachings of the present invention.

Fig. 2 is a front elevation thereof.

Fig. 3 is a diagrammatic view of a pantograph profile grinding machine showing the device4 which is a; graduated circular arc; readings on.,

Which` may be read by .xed pointer member I4.

indicates a` The suce member I3, is within e ways ,comprise ing the strips I 5 and IB mountedion the base.

The position of the slide I3 may be fixed by screw I'I, positioned througheslot I,`andthreadedly en' gaged in base `ID.QThe forwardedge I3'V of: slide' I3, is'concave, and of a curve-of `radiuslarger than the radius of the largest follower wheel for' diSc-IS-to be used. Member` 20, extending from.

the top "of strip" IGQserves asa stop for the shank 2 I, of the follower wheelvIS, and extends frmfthe base to a The device just described,il designated generally, by the numeral `22,.is `mounted on the` pattern table 23, .which` also holds pattern, .ofl thev pantograph `machine 25. Arm 26 of the .pantograph linkage, is' adapted tor'e'ceive theshank 2I of the follower 21; .The numeral 28indicates the grinding wheel, to `which the machine mecha`` nism is adapted'to imparta continuous rotary` motion, and at the will of the operator,.movement along the vertical, besides movement along apath determinedV `by the pattern 24, for operatingv on` the work29, which is mounted in asuitable jig 3.0, on work table 3|.4 `A post.32',=1provided .with a wheel dressing diamond point 133, is secured in` position on either'said work table or jig, for` contact with the grinding wheel 28, when the said grinding wheel is to be dressedr Said device 22,` Vmay be provided with slots f 34, for mounting1v same in any ,suitable'mannen In the particu-1 lar pantograph machinelillustrated, the Vfollower wheel I9, when manually movedin 'any direction: in a horizontal plane,` will cause movement Lof the grindingwheel28 .in an opposite direction of such reduction in' scope asis determined by thev linkage-of the machine 25. l

The operator isprovided with a plurality of followers ofthe type 2l, the shanks` 2| of all ofY which are of identical diameter, while the diam-y i between' the diameter of the follower discyIS l pattern table so that graduations on I2" read near mid-scale, and slide I3 is securedin contact with cam I2', when shank I9 of the Vfollowerll chosen, is in contact with stop ,member 20; andu the-*follower disc I9 is in contact `withlii' ofthe; 5 slide I3, `and diamondpoint33 is4 in contact; with` 'point beyond any position of the slidewith the pattern 24, vvsothat the grinding A'wheel' 28 shallperform -on work 29. l-Test' of the =work by gauges therefore provided, will indicate that the go gage will not fit when the grinding wheel 28 has worn down. This wearing down Vof the grinding wheel, obviously has changed 'the prescribed relationship the grinding wheel diameter should bear to follower ydiscV diameter. 'Ihe next smaller sized follower 21`isfnowrmounted on arm 26, in place ofi-the one just used. The grinding wheel as worn down is of a size too large with respect to the follower wheel now substituted.

In operation, to dress the grinding wheel 28 to proper size, the follower disc I9 is brought into contact with edge I3' of the slide member I3, and slid gently therealong so that shank 2| of the follower 21 approaches the stop member 20, whereupon the grinding wheel l28 is fed into contact with dressing point 33gwhile there is caused to occur relative vertical reciprocatory movement between the grinding wheel 28 and the diamond point 33 by the operator. When shank 2| is in contact with stop 20, and disc I9 is in Contact withslide l3,.and grinding wheel 28, is then dressed to uniform cross-section, its diameter is of proper dimension for use with the follower substituted. Every time the grinding wheel 28 wears down, a next smaller sized follower is substituted, and the dressing down operation repeated. During continuance of the production of the pieces 2'9, should the grinding wheel need replacement, it is initially dressed down by use offits nearest sized related follower, usingthe undisturbed setup V'of the device 22 on machineZS.

, vDuring initial set up, line adjustment of slide position, meaning of member I 3, is effected by aid of slight movement of the cam wheel lI2.

Proper lcontinued working of the device presumes that there is no wear on the diamond point 33. In practice, however, some such wear does occur. The test gages on the work 29 immediately after a redressing `of the grinding wheel 28, will show whether the proper relationship is being maintained between the grinding wheel and the Vfollower used. VIf found at fault, and the .setting had not been disturbed, the discrepancy is due because of wear of the diamond point 33. To

adjust for this, the position ofthe slide is slightlyv altered with the aid of cam I2. Experimentand test with the gages Will 'determine the extent of cam movement, and the'number of Ywork pieces performed will determine the frequency and scope of such adjustment. Discrepancies in initial adjustment, or variations due to any cause `in the associated machine, are likewise corrected by manipulation of the cam wheel 12, and 'slide member I3, which of course shall always be mainbodiment herein be deemed illustrative and not restrictive andthat the patent shall cover all patentable novelty herein set forth and taught; reference being had to the following claims rather than to the particular description and construction herein to indicate the scope of this invention.

Iclaim:V

l. In a precision dressing device for the work grinding wheel of a profiling machine of the pantograph type including a pattern follower VYwheel on a shank carried by the pantograph linkage, a work holding table and a pattern holding table, the combination of a mounting member adapted to be secured on the pattern holding "table, a stop member secured on the mounting member, a pattern follower wheel guide membermovably mounted on the mounting member in a direction along the stop member, means to secure ywheel dressing member fixed on the work holding table in the line kof movement determined by said edge of the guide member; the stop member presenting an edge transverse'said edge of the guide member; theshank of the pattern follower wheel being adapted to contact said edge of the stop member whenV the grinding wheel has been dressed to a predetermined diameter by the dressing member.

v2. A device as defined in claim 1, wherein the guide member adjustment means includes a graduated member adapted to indicate guide member movement accomplished by the adjustment means.

3. In a device as dened in claim 1, wherein the guide member adjustment means comprises a cam rotatably lcarr-ied on the mounting member, and in contact with the guide member.

,4. In a device as defined in claim 1, wherein the guide member is slidably mounted on the mounting member, and has its line of movement parallel to the shank contacting edge of the stop member.

5. In a device as -defined in claim l, wherein the guide member adjustment means comprises a cam rotatably carried von -the Ymounting member and in Contact with `the guide member; a portion of the edge of said cam member being circular and graduated with markings indicative of extent of guide member movement and a fixed pointery on the mounting memberadjacentsaid circular portion.

6. In a device as' defined in claim 1, including graduated means `adapted to indicate guide member movement accomplished by the adjustment means.

7. In a device as 4defined in claim 1, characterized Yin that the path :offered the pattern follower wheel along the mentioned edge Tof the guide Vmember is comparatively long, and the distance between normals V'to the mentioned edge of the stop member from the points of commencement and .end of `said path, iscomparatively short, whereby the dressing memberaction on the grinding wheelis feasily and finely controlled.

f Y NACHEMOV. A 

